Multiple acid pathways in Casco Bay: Implications for the next 25 years J. Salisbury, D. Vandemark, C. Hunt, S. Shellito Modeled -Background -Multiple acid pathways into Casco Bay -Recent observations -Implications for the near future Source: Le Qur et al. 2012; Global Carbon Project 2012Le Qur et al. 2012Global Carbon Project 0.4 PgC/yr 90% + 1.00.5 PgC/yr 10% 2.60.8 PgC/yr 28% Calculated as the residual of all other flux components 4.30.1 PgC/yr 46% 26% 2.50.5 PgC/yr 4 5 CO 2 + H 2 O CO 2 + CO H 2 O carbonate ions Carbonic acid reduces ocean pH. The concentration of carbonate ions decreases. H 2 CO 3 carbonic acid 2HCO 3 bicarbonate ions cmore.soest.hawaii.edu Saturation Index ( ) of the mineral aragonite > 1 animals can make shell >>1 easier to make shell < 1 shell dissolves Ca 2+ ][CO 3 2- ] sp Affected by temperature: Temp corresponds to . Varies with CO 2 : CO 2 corresponds to . Varies with pH: pH corresponds to . Note: